Slamming - FC 22?

[VinnyC]

good morning,

I'm filling in for my other half while he's out of town, so last night our FC levels were 10. It said to add 241 oz. bleach, which I did. this morning, the FC levels are 22. it rained last night, but i doubt that is a factor. I ran the FC tests last night and this morning twice, same result. What did i do? the calculator says not to add anything today...until I test it again at lunch time. am i doing this right?



Thank you,

Kim

 

[Texas Splash]

Hi Kim, We can help, but need to verify a couple things if you can help us:
- With your 13K pool, going from FC of 10 and adding 241 oz (or regular 8.25% bleach) would take you to a new FC of 22.5. So if you are SLAMMing at 22, that may be a good FC.
- We don't know your CYA level though. Do you? That's critical to know if you are SLAMming at the correct FC level. They go together like peas and carrots.

 

[umpalumpajay]

actually, you may have passed the OCLT and not even realized it.

 

[VinnyC]

That would be awesome! CYA is at 30, retook the FC test, which gave me 19. hubby said that we just added the cya agent this past thursday and wanted to wait a week to test the cya levels again, but I wanted to give it to you now to give you more info. our cya levels were at 0 before adding the cya acid.

 

[Texas Splash]

Okay, thanks for the update. So if I understand correctly, your CYA was 30 when it was last tested, but apparently more stabilizer has been added since then (last Thursday). Then just stick close to the Pool School - Chlorine / CYA Chart to always ensure you are always at the proper SLAM FC level. For example:
- At a CYA of 30, your SLAM FC should be 12
- At a CYA of 40, your SLAM FC should be 16

So if you find in the next day or two your CYA increased from the last dosage, you'll want to increase FC accordingly.

Reference that CYA chart and you'll be fine. Also use the Poolmath calculator if you need to so you don't waste bleach.

 

[VinnyC]

Ok, great. thank you!